1. Field of the Invention
The present invention generally relates to a semiconductor laser diode device, and, more particularly, to a semiconductor laser diode device and a method of manufacturing the same, designed to provide excellent heat dissipation, thereby extending the life span of products manufactured from the semiconductor laser diode device, and to reduce the number of components while simplifying an assembly process, thereby reducing manufacturing costs.
2. Description of the Related Art
Generally, a semiconductor laser diode device is operated using electrical properties and optical properties of a p-n junction semiconductor diode adapted to generate laser oscillation by forward current injection, and has various applications including laser pointers, laser printers, scanners, data storage, such as CD-P, CD-ROM, CD-RW, DVD-P, DVD-ROM and the like, and optical pick-up apparatuses.
Such a conventional semiconductor laser diode device is classified into a can-type, and a resin molded lead frame-type according to the shape of the semiconductor laser diode device. Referring to FIG. 1, a can-type semiconductor laser diode device 10 is illustrated, which comprises a laser chip 19 for emitting laser beams, a sub-mount 11 for mounting the laser chip 19 on the top surface thereof, a heat dissipation member 13 protruded a predetermined height from the top surface of a disk-shaped stem 12 for mounting the sub-mount 11, and a plurality of leads 14 extended downward from the stem 12 to be electrically connected to a main substrate (not shown). Each of the leads 14 is electrically connected to the laser chip 19 via a wire 15.
The semiconductor laser diode device 10 further comprises a cap member 16 having an emitting opening 16a at the center of the upper surface thereof and mounted on the stem 12 for protecting the laser chip 19 and the sub-mount 11 from the external environment, and a glass member 17 mounted on the upper surface of the cap member 16, so that the laser beam passes through the emitting opening 16a and the glass member 17.
In such a conventional can-type semiconductor laser diode device 10, the cap member 16 made of metal is assembled to the stem 12, and the glass member 17 is assembled to the emitting opening 16a of the cap member 16 in order to enhance transmittance of light having a specific wavelength. As a result, the assembly process is complicated, and a number of components are required, thereby causing limitation in mass production and reduction of manufacturing costs.
Accordingly, in order to solve the problems of the can-type semiconductor laser diode device as described above, lead frame-type semiconductor laser diode devices constituted by a lead frame and a resin part have been developed, and an example thereof is disclosed in Japanese Patent Laid-open publication No. 2002-176222 (Laid-open Date: Jun. 21, 2002).
The semiconductor laser device of Japanese Patent Laid-open publication No. 2002-176222 comprises a first lead having a mounting portion for mounting a semiconductor laser chip, a second lead for electrodes extended downward in the vertical direction, and a resin member for holding the first and second leads, in which a connecting portion is equipped to the second lead, and connected to the resin member in the longitudinal direction of the second lead.
However, although the above semiconductor laser device has advantages of preventing the leads from being detached from the device upon electrical connection of the leads, and of reducing the size of the products, heat dissipation becomes extremely poor upon operation of the device due to restriction of heat dissipating path and the resin member made of insulation resin having low thermal conductivity. Moreover, foreign substances can be easily attached to the device by virtue of static electricity generated from the insulation resin of the resinous body, thereby damaging the laser chip.
Japanese Patent Laid-open publication No. 2003-110181 (Laid-open Date: Apr. 11, 2003) discloses a semiconductor laser device, which comprises a substrate having an opening and a conductive support for mounting a semiconductor laser chip, and first and second leads, wherein, with the second lead inserted into the opening, a resinous block fills the opening such that the leads are integrally fixed to the conductive support.
Although the semiconductor laser device of Japanese Patent Laid-open publication No. 2003-110181 has an advantage of reducing the number of components in comparison to the cap-type semiconductor laser device, the separate support must be prepared, and assembled to the lead, complicating the manufacturing process, and making it difficult to reduce the manufacturing costs. Additionally, since the insulation resin is configured to surround the semiconductor laser device, problems caused by attachment of foreign substances due to the static electricity remain.